Python基礎概念2

標籤：

 1.bool變數及運算

print 1 + 1 == 2
print 1 + 1 != 2

print 1 + 1 == 2 and 1 + 1 == 3
print 1 + 1 == 2 or 1 + 1 == 3

print not 1 + 1 == 2

print 1 in [1, 2, 3]  輸出: True
False
False
True
False
True  2.iflight = "red"
if light == "red":
    print "Stop!"
elif light == "green":
    print "Go!"
elif light == "yellow":
    print "Slow down!" 3.whilea = 100while a<100:         a = a +1print a 4. for in

contact = {"Li Lei" : "1303030", "HanMeimei" : "1450303"}for i in contact:    print i, contact[i]

輸出： 

"Li Lei" : "1303030"

"HanMeimei" : "1450303"

5.break continue意思與其他大部分語言相同 6.自訂函數def addNum(num):
     a = 0
     for i in num:
          a = a + i
     return a

num = [ 1 ,3 ,4 ,5 , 9]

print addNum(num) 7.函數範圍與C++很像 x =  0
y = 0
def changex():
     global x   //global 可以在函數裡面使用函數外面的變數
     x = 10
     y = 10
     print x
     print y
changex()
print x
print y  8.importimport math  //匯入包

print math.pi

print dir(math)  //dir可以查看包的所有方法 

Python基礎概念2